Connecting rod



Dec. 2, 1930. A. w. KJELLBERG 1,783,922

CONNECTING ROD Filed March 9. 1928 gnuemto'v aw iZ Zfe/Yl zy Patented Dec. 2, 1930 UNITED STATE Se ANDERS W. KJELLBERG, orv DETROIT,

ro m'rion, or-nnraorr, MICHIGAN, ,A coaroaarroiv or DEL W RE r CONNECTING Ron Application mama-ah. 9, i928. i srrariitd. aces 15ft! My invent-ion relates to connecting rods" and more particularly to an improved man ner of forming therein a passage torconducti ing lubricant fromthe crankshaft bearing 5 to the Wristpm bearlng. Ithas been'found necesssary when formlng an 01].. passage in a connecting rod, to add-metal around the pas sage for-strengthening purposes. This increases the weight of the rod which is very undesirable. 7

An object of my invention is to provide a connecting rod in which the oil passage is so located that the weight of the-rod isjnot increased over that of a rod ofsimilar size,

is a section on the line of ing a webportion 10 and flange portions 12 and 14:. At the end 16 the rod isqenlarged to form a bearing adapted to be clamped agalnst the crankshaft by'a cap 18, in the usual manner. Theopposite end 20 is provided with an opening'22, in which the usual wrlst p n is journalled. In order to properly lubricate the Wrist pin, it is desired to conduct lubricant from a passage in the crankshaft to the wrist pin Thishasbeen done in the past by forming a hole in the center the connecting rod web, and adding material to the web around the passage to strengthen the rod. This hasv always resulted n inereaslng the Weight of therod, which is undesirable because it tends to cause the enginefto vibrate" at certain speeds. Also, pipes have been con- F nected between the crankshaft bearing and the wrist pin bearing, on the outside of the rod, to conduct lubricant up to the wrist pln bearing. This is objectionable because due to the veryhigh speeds atwh1clrtherod opcrates, the pipe is apt to be torn loose from the rod by the action of inertia force.v

AT T,

IGANQAssIGNoa'ro GENERA Morons 0 a. 7

.In order to-Yovercorne these objections, I

propose to locate the passage-fll substantially at thejunction of the web 1 0 and the flange portion 141' In order not" to reduce the strength of the rod, it is necessary to enlarge the usual fillet as at 26 when forging the rod. The passage 24: is then drilled in the position illustrated in Figure 3. The proportions of the rod are so calcu'latedthat the amount of material removed in drilling thepassage 24, will at least offset the added Weight caused by the enlarged fillet '26, while at the same time not decreasing the structural strength.

of the rod. :By locating the passage as shown, I V the enlarged fillet serves to increase the y strength of the rod much more than ifa corresponding amount of metal were added at the center or neutral axis of the rod It will be readily seen that since the neutral axis is the point of least stress,metal added to this point will not increasethe strength of the rod materially.

The result is that I obtaina 1 0d which'is not any heavier than a standard rod of similar size in which there is no oil passage. In fact, 'I have "found that my improved rod actually weighs less than a similar rod without an oil passage, and that dueto its changed shape, it ard rod. i 7

It is thought that from the foregoing taken is actually stronger than a standin connection with the accompanying drawing that the construction and operation of Y the device will be apparent tothose skilled in the art,'and that various changes in size, shape, andproportion and details of con- 'struction. may be ma-dewithout departing i from the spirit and scope ofthe appended claims.

:Iclaim: ,7 1. A connecting rod having a web and flange portions, and a lubricant conductin bore formed in said rod substantially at t h e junction of said web and one otsaid flange portions. V

'- 2. A connecting rodhaving a weband flange portions, and alongitudinally extending lubricant conducting passage formed 1n said rod adjacent one of said flange portions, 190,

said passage being surrounded by metal so that it is closed except at its ends.

3. A connecting rod having a Web and flange portions, an enlarged fillet portion connecting said Web and one of said flange portions, and a lubricant conducting passage formed in said fillet portion, the increase in Weight due to said enlarged fillet portion being offset by the material removed in forming said passage.

4. A connecting rod of I-beam cross section, having formed therein a lubricant conducting passage extending from end to end of said rod and located at a point well re moved from the neutral axis of said rod, said passage being closed except at its ends.

In testimony whereof I aflix my signature.

ANDERS W. KJELLBERG. 

